Efficacy of five nematicides against root-knot nematode when applied via single and double drip tapes in a Florida sandy soil.

Background: The efficacy of drip-applied nematicides depends on adequate product distribution, which can be difficult in sandy soils. Three new non-fumigant nematicides (fluazaindolizine, fluensulfone, fluopyram), together with two old nematicides, oxamyl and metam potassium, were evaluated when applied via single and double drip tapes to control root-knot nematode in cucumber and squash in Florida between February 2020 and December 2022.

Results: Nematicide applications via double drip tapes resulted in lower root gall infection (and tend to have higher yield) as compared to a single tape for fluopyram, but no difference was noted between single and double tapes for oxamyl and fluazaindolizine. Fluensulfone response was somewhere in between and metam potassium had higher squash yield when applied with double tapes. Root-knot infection was higher in cucumber than in squash, and metam potassium had the highest yields and lowest nematode infection compared to other nematicide treatments.

Conclusion: The benefit of double versus single drip tapes depended on the type of nematicide that was applied and was evident for nematicides that have poor water solubility like fluopyram. Some benefit was noted for metam potassium, but no or limited benefit was noted for oxamyl, fluazaindolizine and fluensulfone. © 2023 Society of Chemical Industry.